<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>字符串形式的ref</title>
</head>
<body>
  <div id="test"></div>

  <script crossorigin src="https://unpkg.com/react@16/umd/react.development.js"></script>
  <script crossorigin src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
  <script src="https://unpkg.com/babel-standalone@6/babel.min.js"></script>
  <script src="https://cdn.staticfile.org/prop-types/15.6.1/prop-types.js"></script>

  <script type="text/babel">
    class Demo extends React.Component {
      render() {
        return (
          // 给组件标签绑定ref，组件的实例对象上有个属性叫做refs，组件标签上绑的ref值就会显示在refs中
          <div>
            <input ref="input1" type="text" placeholder="点击右侧提示数据" />&nbsp;
            <button onClick={ this.clickData }>点击提示左侧输入的数据</button>&nbsp;
            <input ref="input2" type="text" placeholder="失焦后提示数据" onBlur={ this.blurData }/>
          </div>
        )
      }

      clickData = () => {
        const { input1 } = this.refs
        alert(input1.value)
      }

      blurData = () => {
        const { input2 } = this.refs
        alert(input2.value);
      }
    }
    ReactDOM.render(<Demo />, document.getElementById('test'))
  </script>
</body>
</html>